I hate to parrot Slashdot, but this article from Ars Technica discusses the sources and legitimacy of the common figures used to support the further restriction and enforcement of copyright and other IP protections. It's a really good read.

In essence, the figures of 750,000 jobs and 250 billion dollars "lost to piracy" have been quoted and re-quoted for years in lobbying efforts, testimony, articles, and more in an effort to get tougher IP laws. Unfortunately, no one ever followed the breadcrumb trail back to the original source of the figures or did any simple reality testing of them until now... and the numbers don't really hold up to scrutiny. Do you like your government making laws based on flimsy statistics? I don't.